SUBSECTION 5D
HYDRAULIC COMPONENTS
A. Check the special marks on the spool and valve bore to
5. Remove spring (20) and spacer (19).
ensure correct assembly.
6. Slide spool (17) from the valve body with push pins (16
B. Insert the heads of push pins (16 and 18) into the spool
and 18). Remove the push pins from the spool, then mark
before installing the spool into the valve body.
the spool as noted below.
C. Check for secure installation of snap rings (09 and 25).
NOTE
D. Complete the wiring connection of the solenoid at in-
Certain spool types are not symmetrical. To provide
stallation.
correct assembly, it is recommended that the spool
and body be marked with a metal scribe. The spool
INSTALLATION. To install the solenoid valve, proceed as
should be marked on the minor diameter, not across
follows:
the sealing lands.
1. Place O-rings (04) in the ports at the bottom of the valve
body if not already done. Now set the valve on the subplate
CLEANING. The importance of cleaning the valve and all its
or manifold in its correct position and secure with the four
parts can not be overemphasized. All parts must be thor-
socket head screws.
oughly cleaned and kept clean during inspection and as-
sembly. The close tolerance of the valve body and spool
2. Install the terminal block and gaskets (33) in position and
makes this requirement more stringent than usual. Clean
complete the wiring of the solenoid. Then attach the ground
all removed parts, using commercial solvent that is com-
wire of gasket (02) and install plate (01) and fasten with the
patible with the system fluid. Compressed air may be used
screws (31).
in cleaning the valve, but it must be filtered to remove water
3. Bleed the system of air as described in Subsection 5A.
and contamination. Clean compressed air is particularly
useful in cleaning the spool orifices and body passages.
4. Connect the battery cable, start the engine, and check for
leaks. If none, test the valve for proper operation.
INSPECTION AND REPAIR. Inspect, repair, and replace the
valve and all its parts as follows:
SHUTTLE VALVE (36Z1171)
1. Visually inspect the internal bore of valve body (05) for
DESCRIPTION. Shuttle valves are used in several places in
scratches or erosion across the spool land sealing areas. If
the system to direct the flow of hydraulic fluid into a
scratches or erosion are found, replace the complete valve.
common line from either of two other lines. When pres-
surized oil is available at either of the side ports, the float-
ing piston (shuttle) moves to the opposite side of the valve to
close the opposite side port. Oil is allowed to flow out the top
Do not stone the edges of the sealing lands on
port to a common line.
the valve spool. Rather, use a 500 grit abrasive
REPAIRS. The shuttle valve is considered non-repairable. If
paper to remove any burrs found on the spool.
the valve is faulty, the complete valve should be removed
Use the paper very lightly on the outer
and replaced with a new valve.
diameter of the spool only.
REMOVAL. To remove the valve, proceed as follows.
2. Inspect the spool for burrs or small scratches. If any are
found, remove them with 500 grit abrasive paper. Then in-
1 . See General Removal at the beginning of this section.
sert the spool into the bore, rotate it while moving it back
2. Disconnect the hydraulic lines at the valve and position
and forth to check for binding. If any binding or side move-
the lines to avoid interference as the valve is removed. Cap
ment exists, the spool must be replaced.
the lanes to prevent the entry of contaminants.
3. If a new spool (17) is required, use a very fine grit stone to
3. Remove the two capscrews which secure the valve. The
break the feathered edges of the balancing grooves. Use
valve can now be removed.
500 grit paper to lightly polish the outside diameter of the
spool.
INSTALLATION. To Install the valve, proceed as follows.
4. Inspect all the other parts for wear or damage and re-
1. Position the valve and install the two capscrews. Fully
place as necessary.
tighten the capscrews to secure the valve.
2. Remove the protective caps and connect the hydraulic
5. Check the grooves where any seals are placed; grooves
lines to the valve.
and detents should be free of any rough edges to prevent
damage to the new seals on assembly.
3. Connect the battery cable. Start the engine and operate
6. Perform a continuity check on the solenoid coil. The coil
the controls. Observe the valve for leaks, binding or other
should have a resistance value of 24 ohms.
defects.
ASSEMBLY. To assemble the valve, proceed as follows:
SWIVELS (44Z2058)
1. Lubricate all the parts and O-rings with clean hydraulic
DESCRIPTION. Swivels are provided at the input end of the
oil to aid in assembly and provide initial lubrication.
hydraulic lines to clutches and brakes wherever required. A
2. The assembly of the valve is basically the reverse of the
swivel is also provided on the rotary joint for the propel
brake. The swivel allows hydraulic fluid to flow into a
disassembly procedure. The following items require special
rotating member to apply a clutch or brake.
attention:
5D-7
